Pipe-line recovery device



May 17,A 1949. B. D. MARKS ET Al.'

PIPE LINE RECOVERY DEVICE Filed Marh 24, v1947 IN V EN TORS a D MARKS o. E. DILLONv FlG. 4-

ATTQRNEY Patented May 17, 1949 PIPE -LINE RECOVERY DEVICE Ben D. Marks and Orel Elton Dillon, Corpus Christi, Tex.

Application March 24, 1947, Serial No. 736,696

This invention relates to a devic'e for unearthing pipe lines, and has for its principal object the removal of pipe lines buried in the ground without the necessity for the removal of the over-lying earth.

An important object of the present invention is to provide a recovery device which is very simple in construction and which is highly emcient in operation, by which the recovery of buried pipe lines may be accomplished very rapidly and with minimum expense.

Other and more specific objects and advantages of this invention will become apparent from the following detailed description when read in conjunction with the accompanying drawings which illustrate a useful embodiment in accordance with this invention.

In the drawings:

Fig. 1 is a side view of the pipe recovery device in accordance with this invention showing the same in use;

Fig. 2 is a view looking down on the surface of the ground to illustrate the only portions of the device which are visible duringr the pipe recovery operation shown in Fig. 1;

Fig. `3 is an enlarged side elevation of a portion of the pipe recovery device, showing some of the details thereof; and

Fig. 4 is an end elevation along line 4 4 of Fig. 3.

Referring to the drawings, a pipe line, indicated by the numeral IU, is shown buried below the surface of the ground. Such pipe lines may be buried at depths ranging to several feet and normally will be made up of pipe sections coupled together in various ways, as by means of collars II, or by welding the ends of adjoining pipe sections. Shown in position on the pipe is the recovery device in accordance with this invention which consists of a tubular sleeve I2 which surv rounds the pipe, having an internal diameter which is somewhat greater than the external diameter of the collars I I or other connections employed in coupling the pipe sections. The forward end of sleeve I2 is internally bevelled at I3 to form a sharp circular cutting edge, which may be hardened in any suitable manner, or faced with a suitable hard material, such as tungsten carbide, Stellite, or the like, which will resist abrasion while maintaining the sharpness of the cutting edge. The internal bevelling forms an annular rearwardly and upwardly sloping surface which will serve to guide the projections, such as are formed by the edges of collars II or welding beads, into the interior of sleeve I2 as it is moved over the pipe line in the manner to be described hereinafter. Rigidly mounted on the upper surface of sleeve I2 near its forward end, is a pair of upstanding laterally spaced, parallel plate members I4-I4. As best shown in Figures 1 and 3, the leading edges of the plate members I4-I4 lie in a plane extending at approximately a right angle to the longitudinal axis of the tubular sleeve I2. A metal blade member I5, of generally flat rectangular shape, has one end pivotally connected between members III-I4 by means of a bolt I6 which passes transversely through the Aplate members and the end of the blade member.

Blade member I5 is of such length as to extend, when in use, from the top of sleeve I 2 to a point somewhat above the surface of the ground. The length of blade member I5 will, of course, be varied to conform to the depth at which pipe line Ill is buried. The forward edge I'I of blade member I5 is sharpened throughout its length and suitably hardened, as by facing it with a hard abrasion-resisting material of the kind previously mentioned. .The thickness and width of blade member I5 are generally sufficient only to make the blade reasonably rigid and resistant to bending or twisting in operation. A link I8 is pivotally attached to the upper end of blade member I5 for attachment of a pulling cable I9 which extends forwardly to a suitable source of power, such as a power driven winch 20, shown mounted on the end of a truck 2| which is movable over the surface of the ground along the pipe line. Cable I9 may, of course, be connected to the draw-bar of a tractor or to any other suitable source of power adapted to apply a strong pulling force to the cable.

The recovery apparatus is employed to recover buried pipe in the following manner: A hole, commonly termed a bell hole (not shown), will be dug to uncover a portion of the pipe line at which the recovery operations are to be begun and the pipe will be cut to provide a free end over which sleeve I2 will be slipped with the bevelled end I3 facing in the direction in which the sleeve is to be moved. Blade member I5 will extend above the surface of the ground having its cutting edge I'I likewise facing in the direction of movement of the recovery apparatus. Cable I9 will be connected to the upper end of blade member I5 and the winch 20, to which cable I9 extends, will be set in operation to draw blade member I5 through the ground, or the truck or tractor will be moved forwardly to apply the required pulling force to cable I9. Blade member I5, because of its relatively thin flat form and sharpened leading edge will cut through the earth overlying the pipe line under the pull applied through cable I9 by the power source. By virtue of its pivoted connection to sleeve I2, blade member I5 will slope forwardly in the direction of the applied pulling forc'e to produce a shearing action which will greatly assist the blade edge to cut through the earth. The pull applied to blade member I5 will, of course, be transmitted" to sleeve I2 which will be drawn over the outer surface of pipe line I and will cut an annular channel concentrically about the pipe line through the surrounding earth, displacing the latter annularly from the surface of the pipe line. When sleeve I2 has progressed a suitable distance over pipe line I9, another bell hole (not shown) Willbe dugto uncover the pipe line adjacent the point which.

the recovery device has attained and the pipe line will again be cut. The severed section of the pipe line may then be withdrawn bodily longitudinally out of. the annular channel cut by sleeve I2 through either of the bell holes. This may be done by attaching cable I9 to one of. the ends of the pipe and using the same power sourcepreviously used for pulling the recovery apparatus over the pipe line, the pipe will be pulled out of the ground. An independent power* source may be used for this purpose if desired.

With the recovery apparatus described, buried pipe lines may be easily and quickly removed from the ground without removingV any of the overburden, except of course, such as is removed in digging the bell holes. The stripping ofthe pipe can be performed as rapidly as the source of `pulling power is moved over the ground. By the use of a single blade member of the thin knife-like form described, only a relatively small proportion of the total power applied will need to be'expended in drawing blade member I throughv the earth, as no earth is removed by the blade member which merely cuts a thin slit through the earth as it is drawn forwardly. Consequently; the major proportion of the applied power will be exerted through blade member I5 to draw sleeve I2 over the pipe line. rIhe sharp edge I.'I of the blade member will permit it to cut easily through tree roots and other vegetation commonly present in the over-burden above the pipe line. Although such overburden will be material which was used toback-ll the pipe trench when the pipe line was originally laid and may therefore, not be quite so dense as the earth formations adjacent the original pipe trench, such material will often become quite dense and hard-packed, particularly if it has been in place for a numberof years as is frequently the case. Nevertheless, even in the latter event, the recovery device in accordance with this invention will be able to cut through such dense materials with relative ease and rapidity.

Pipe lines of variousl diameters may be recovered by use of the device in accordance with this invention, it being necessary only to vary the diameter of sleeve I`2 to correspond with the diameter of the pipe to be recovered. In general, the inside diameter of sleeve member I2 will be made about one inch greater than the greatest external diameter of the pipe lineon which it is vile of this patent:

'4 to be used. This difference may be varied somewhat depending on operational conditions. For example, if the overburden is sandy, the sleeve may be made somewhat larger in diameter because of the tendency of sand to pack. Where the overburden is a gravelly material smaller clearances may be preferable to prevent admittance of relatively large pebbles to the interior of the sleeve. The length of sleeve I2 will like- Wise be subject to variation, depending upon conditions encountered. Generally, the length of sleeve I2 Will be great enough to prevent its bindingv on thepipeline as it is drawn over the line.

As indicated above, blade member I5 will generally= be ofsuch thickness and width so that it willV be substantially rigid in use. In most cases, this result can be 'obtained by means of a blade ranging from one-half to three-quarters of an inch in thickness and from about four to twelve inches in Width, the length, as indicated, being such as may be requiredto extend from its point o'f connection to sleeve I2" to above, the surface or' the`V ground wheni'n use.

It'will be understoodithat other alterations and changes may be made in the details of the described recovery apparatus within the spirit oi this invention but without departing from. the scope of the appended claim.

What we claim and desire to secure by Letters Patentis:

A device for' recovering'buried pipe, comprising,

4a tubular' sleevemember adapted to encircle a pipe and to be slidablei longitudinally over sain pipe, said sleeve: member having a. sharpened leading edge, a Vsingle flat, rigid blade member centered above said sleeve member and extending upwardly therefrom to above the surface of the ground overlying said pipe; said blade member having its leading edge sharpened' and hardened toI resist abrasion,- a: pivotal connection between the lower end of said blade member and said sleeve member; said connection consisting of a pair of spaced parallel" plate members arranged on opposite sides ofzsaid'bla'demember and rigidly connected to said sleeve memberV and a pivot pin extending transversely through said plate members and saidblade member, the leading edges of said parallel plate members lying. in a plane extending at approximately a right angle to the longitudinal axis of said sleeve member whereby earth is deflected substantially laterally by said plate members andfsaid blade member, and means for connecting a pulling force to the upper end of said. blade member'.

BEN D; MARKS. OREL ELTON DILLON.

REFERENCES CITED The following references are of record in the UNITED STATES" PATENTS Number Name Date 1,808,974 Wilkens June 9, 1931 2,129,453 Van Sickle Sept. 6, 1938 2,386,615 KnappV Oct. 9, 1945 2,396,849 Herbert Mar. 191946 

